1. Field of the Invention
The present invention relates to an apparatus and concomitant method for providing a volume control with DC supervision and an alarm by-pass circuit in an emergency voice evacuation system. More specifically, the present invention provides a volume control that allows users to control the volume of paging and background music while maintaining supervision in an emergency voice evacuation system.
2. Description of the Related Art
An emergency voice evacuation system for a facility is often designed to drive a certain number of notification appliances, e.g., audio notification appliances, visual notification appliances and both audio and visual notification appliances. In operation, paging and/or background music can be implemented into the emergency voice evacuation system as well. Volume control of each zone of the emergency voice evacuation system is desirable when the system is used for paging and/or playing background music during non-alarm conditions.
However, when using a volume control in an emergency voice evacuation system, the volume control must be able to pass DC supervision. Volume controls currently used in emergency voice evacuation systems may not be able to provide continuous supervision of the emergency voice evacuation system when they are not properly used, e.g. when the volume control switch is placed at certain settings, such as for example, when the volume control is moved in between two consecutive nodes or at a last unlabeled node of the volume control. Consequently, in such positions of the volume controls currently used, a voice evacuation panel may erroneously detect that supervision is lost when, in fact, there is nothing wrong with the circuits of the emergency voice evacuation system. Unfortunately, when the volume control is improperly set, an alarm or alert is generated requiring a technician to respond immediately. The technician may be required to come on site to simply move a switch on the volume control to a proper node, thereby wasting valuable time and resources.
Thus, there is a need for a method and apparatus for providing volume control with continuous DC supervision and an alarm by-pass circuit in an emergency voice evacuation system that is capable of maintaining supervision at any setting of the volume control.